This application claims priority under 35 U.S.C. §119(a) on Patent Application No. 2010-89472 filed in Japan on Apr. 8, 2010, the entire contents of which are herein incorporated by reference.
The present invention relates to fixing devices that fix toner images formed on recording paper, and to image forming apparatuses including the same.
This type of fixing device is applied in image forming apparatuses that use methods such as electrography, electrostatic recording, and magnetography or the like, and sandwich between a pair of fixing rollers a recording paper (such as plain paper, electrostatic recording paper, and photographic papers or the like) on which a toner image has been formed, thereby applying heat and pressure to fix the toner image onto the recording paper.
In these fixing devices, the recording paper sometimes winds around the fixing roller, and therefore the leading edge of a peeling plate is positioned near a peripheral surface of the fixing roller such that recording papers are peeled off from the fixing roller by the peeling plate. For example, in JP 2002-287553A (hereinafter referred to as patent document 1), the peeling plate and a member that backs up the peeling plate are integrated such that the peeling plate is supported and positioned. Furthermore, in JP 2002-91222A (hereinafter referred to as patent document 2), the peeling plate is supported and positioned by being laser spot welded.
In this regard, it is necessary for the leading edge of each of the above-mentioned peeling plates to be positioned near the peripheral surface of the fixing roller. However, when a blockage (jam) of recording papers occurs in the vicinity of the peeling plate of the fixing roller such that transport of the recording paper is interrupted and the peeling plate is pressed on by the recording paper, sometimes the leading edge of the peeling plate pushes against the surface of the fixing roller such that the surface of the fixing roller is damaged.
With the structures of the fixing devices of patent document 1 and patent document 2, it is probable that the leading edge of the peeling plate will push strongly against the surface of the fixing roller, and no countermeasure is devised against this problem.
Accordingly, the present invention has been devised to address the above-described issue, and it is an object thereof to provide a fixing device and an image forming apparatus provided with the same in which damage is not caused to the surface of the fixing roller by the leading edge of the peeling plate even if a jam occurs.